The invention is particularly useful in, but not limited to, recording systems, e.g. systems for recording digital information. A recording system is described below as one example of the background of this invention.
In a recording system including multiple recording devices it is advantageous to include a device that acts as a spare to be used in the event that one of the other devices is not available for any reason such as failure of a device or the device being offline or unavailable due to some other cause. The spare device is extra or redundant, and thus may not be used during normal system operation, except in the event that another device is not available, in which case it is no longer spare. One option to support this redundancy is a so-called N+1 schema. In such a schema there is one device that backs up all of the other N recording devices. This device is designated as “spare” and the others are designated “normal”, e.g. active. In this scenario “normal” means not spare, e.g., performing normal day-to-day operations associated with that device. A spare device is configured to take over the operations of another device if that device fails or is not available for any reason. A spare device may also be referred to as a “back up” device. The “normal” devices are configured to record certain incoming information and may also be referred to as “active, or “in use” or “operational”.
The provision of a spare device in this way is not limited to recording systems. Other systems comprising multiple devices may benefit from the provision of a spare device to be used in the event that one device in the system is not available.